Drive unit for boats



Jan- 19, 1965 K. M. ARMANTRoU'r ETAI. 3,166,040

DRIVE UNIT FOR BOATS Filed NOV. 2l, 1960 Jan. I9, 1965 DRIVE UNIT FOR BOATS Filed Nov. 21. 19.60

14 Sheets-Sheet 2 f'ff DRIVE UNIT FOR BOATS 14 Sheets-Sheet 5 Filed Nov. 2l, 1960 NWN MQ ,m #z Sx q l .SN N lv \\MM\\\ ,NQ Rmx.. w Sa. had @mw m. nu@ /l wn@ mo Kw@ Jam 19 1965 K. M. ARMANTROUT ETAL 3,166,040

DRIVE: UNIT FOR Bons Filed Nov. 2l, 1960 14 Sheets-Sheet 4 y! I 290 266 266 7N 24g il? "f 3- f-Erv'lj J 225 fnverzfs.' jg .'nneMrman-oui womld Zllfflel 25g/f 6. y

Jan. 19, 1965 K. M. ARMANTRoUT ETAL 3,166,040

DRIVE UNIT FOR BOATS vFiled Nov. 2l, 1960 14 Sheets-Sheet 5 Jan- 19, 1965 K. M. ARMAlxrrRouT ETA; 3,156,040

DRIVE UNIT FOR BOATS 14 Sheets-Sheet 6 Filed Nov. 21, 1960 NMA Jan. 19, 1965 K. M. ARMANTROUT ETAL 3,166,040

DRIVE UNIT FOR BOATS 14 Sheets-Sheet 7 Filed NOV 2l, 1960 Jan. 19, 1965 Filed NGV. 2l. 1960 K. M. ARMANTROUT ETAL DRIVE UNIT FOR BOATS 14 Sheets-Sheet 8 fraz/anfora.

Jan. 19, 1965 K. M. ARMANTROUT ETAL 3,165,040

DRIVE UNIT FOR BOATS Filed Nov. 21. 1960 14 sheets-sheet 9 Jan. 19, 1965 K. M. ARMANTROUT ETAL 3,165,040

DRIVE UNIT FOR BOATS Filed NOV. 2l, 1960 14 Sheets-Sheet l0 Jan. 19, 1965 K. M. ARMANTROUT ETAL 3,166,040

DRIVE UNIT FOR BoATs Filed. Nov. 21, 1960 14 Sheets-Sheet l1 Jan. 19, 1965 K. M. ARMANTROUT ETAL 3,166,040

DRIVE UNIT FOR BOATS Filed Nov. 21, 19Go y 14 Sheets-Sheet 12 waorazld ZU. lbel Jan. 19, 1965 KQ M. ARMANTROUT ETAL 3,166,040

DRIVE UNIT FOR BOATS Filed Nov. 21, 1960 14 sheets-sheet 15 Jan. 19, 1965 K. M. ARMANTROUT ETAL 3,166,040

DRIVE UNIT FOR BOATS Filed Nov. 2l, 1960 14 Sheets-Sheet 14 3,166,040 DRIVE UNli` FOR BOATS Kenneth M. Armantrout andDonaid W. Kelhei, Muncie, Ind., assigner-s to Borg-Warner Corporation, Chicago, iii., a corporation of Iliinois Fiied Nov. Z1, 196i), Ser. No. 70,616y 17 Claims. (Ci. 11S-41) This invention relates to a drive unit for boats and more particularly, to a stern drive unit mounted on the exterior of a boat and driven by an inboard engine.

In the propulsion of boats, a drive unit is utilized which usually comprises either a 2-cycle outboard motor and propeller unit mounted on the transom of the boat or a 4-cycle inboard engine with a propeller shaft through the bottom of the boat. Although the outboard method is advantageous to the extent that it is more portable, will kick-up upon striking an obstruction, has an adjustable thrust line, and has a direct steering effect; it hasnut rnerous disadvantages. In particular, it usually has. some what limited steering angle, sizable inerta which resists kick-up, lower engine eiiiciency, poor weight distribution and considerable transom strain. Although the usual 4- cycle inboard engine is advantageous to the extent that it provides better efficiency than the 2-cycle outboard motor, more desirable Weight distribution and no transom strain; it is nevertheless disadvantageous in that it has even more limited steering characteristics,y no kick-up upon striking an obstruction, a -forward inclined engine mounting and a fixed thrust line.

Both the outboard and the inboard types of boat propulsion individually present unavoidable inherent advantages and disadvantages which effect efficiency and safety in a manner characterized by the specific type of drive repre-V sented thereby. lt is therefore extremely important to be United States Patent() able to propel a boat in a manner Whichsimultaneously f provides the advantages of both the inboard and outboard types of propulsion While minimizing the disadvantages of each.

It is a primary object of this invention to provide an improved outboard marine stern drive unit adapted to be driven by an inboard engine for propelling a boat in a highly versatile controllable, eiiicient and safe manner.

Another object of this invention is to provide an outboard marine drive unit driven by an inboard engine, having a propeller thrust line which is angularly adjustable in a vertical plane and which permits unlimited propulsion and steering in any position. Y

Still another object of this invention is rto provide a marine stern drive unit driven by an inboard engine, having low inertia kick-up operative upon striking an obstruction which `does not interrupt the` power transmitted therethrough. v Y

Y Another object of this invention is to provide a marine stern drive unit driven by an inboard engine, having an 1 worm gear raising mechanism and the drive unit casing; j

FAICC,

An additionalA object of thisinvention is to provide an outboardmarinek drive unit having4 all of the above ob-v jects andv providing a gear'reduction drive' train having all drive shafts thereofintersecting a single axis angularly adjustable in a vertical plane.

This invention consists of .the novel constructions'arrangements, and devices to 'be'hereinafter described vandV claimed for carrying out theabove stated objects and such other objects as will be apparent from the following description of preferred forms of 'the invention, illustrated with reference to the accompanying drawings, wherein:

FIG. l is a sectional View taken along line 1 1 of FIG. 2 showing a shiftable outboard marine drive' unit and the inter-relationship of body casings thereof; y

FIG. 2 isa partial sectional view taken along line 2 2 of FIG. 1 showing forward and reverse elements of the outboard unit and a reverse lock linkage therefor;

FIG. 3 is a partial sectional view taken along line 3 3 of FIG. 2 showing a steering mechanism and 4shift-ingA linkage for the drive unit;

FIG. 4 is a partial Sectional view taken along line y4 4 of FIG. 2V showing the shifting linkage with the interconnected reverse lock mechanism and an adjustable kick-up mechanism;

FIG. 5 is a partial sectional view taken along line 5 5 Aof FIG. 4 showing the reverse lock linkage and position- -ing detent therefor; Y j

FIG. 6 is a side View of the driveV unit showing a ratchet raising means and a releasable adjustable lock interconnected' therewith; v

FIG. 7 is a partial side view of the drive unit illustrating the inter-relationship between the adjustable releasable Y FIG. 11 is a partial sectional View of the Worm gear raising mechanism showing the mechanism with the drive unit in an intermediate raised position; Y FIG. l2 is a partially sectioned side view of the drive unit showing the shifting linkage for the drive train and adjustable positioning index mechanism which releasably f' holds the unit in a selected down position and allows the unit to kick-up-and returnl directly to the selectedreleasably held position.'

A further object ofthis invention is to provide a mariney stern drive unit driven by an inboard engine, having ,a

kick-up which is automatically locked 'against movement l vshift linkage;

an interconnected adjustable reverseilock; p FIG. 13 is/a partial sectional View taken along line 13 13 ofmFIG. 12 show-ing a rear view'ofgthe reverse lock and break-away mechanism;

FIG. 14 is a partial sectionalvi'e'w taken alongline 14- 14 of FIG. lSshowing the top of the reverse lock and break-away mechanism;

FIG. 15 is a partial sectional View taken along'line 15 15 of FIG. 12 showing a detent for positioning Vthe FIG. ljis a partial lside viewof a 4 modified reverse lock in its released position; 1 Y Y FIG. 17 'is a partial sectional View taken along line 17e-17 of FIG. 16 showing the modified4 reverse lock and break-away detent; i

. FiG. 18 is a partiallysectioned side view of a'modifed version of the 'drive unit showing the unit mounted di-' rectly on the engine through the transom;

FIG. 19 isi a .partial` sectional View taken along line Q 19 19 of FIG. 20 showing a modified shift linkage;

A further object of this invention is to provide van outboard marine drive unit which can be driven bya horizontally mounted forward inboard engine, which does not require utilization of a universal joint or offset mounting of the propeller drive train.

.FiG. 20 is a partial' sectional view taken alongV line 2 20 of FIG. 24showing the modified shift linkage in i neutral position;

FIG. 2l is a partially sectioned view taken along line 21 21 of FIG. 19 showing a spring-biased lost vmotion device utilized in the modified shift linkage;

which Y teeth 21 of the driving bevel gear-20.

FIG. 22 is a partially sectioned view takenalong line 22-22 of FIG..24; .Y

FIG. 23 is a partial top view of thestern drive showing the external elements of the modified shift linkage;

FIG. A24is apartial side view ofthe sterndrive show- .ingamodied reverse lockmechanism thereof 'A FIG.25` is a side view of a modified drive unit showmg the unit coupled with a transmission and illustrating a "hydraulic'reverse lock;

t head casing 12 is rigidly mounted Yto a boat transom 15 adjacent an opening 16 in the transom. A bearing reshowing a `hydraulic reverse lock actuthe left so that the clutch teeth 47 thereof are in engage,`

tainer 17 is rigidly mounted in an opening 1S in the head casing 12 by bolts 19 and extends into the opening 16 in the transom. A drivingbevel gear V20 havinga set of teeth 21 isrotatably supported in the bearing retainer 17 by bearings 22 and 23. The driving bevel gear 2t) has a drive shaft 24 extending therefrom beyond the bearing 22 and into the opening 16 in the transom. Thedrive shaft. 24 has a splinedend portion 25 which provides a means for coupling the drive shaft 24 with the inboard engine.

. .A pair of bearinglretainers 29 (FIG. 2) are rigidly mounted on opposite sides of the head casing 12 by -a Y set'of bolts 30. 'j The retainers 29 retain a pairof aligned ball bearings 31 in the head casing 12. A reverseV drive 40 and adapted to move axially thereon. n 'llaeshift collar` .45,has a set of reverse clutch teeth 47 which are engage.

able with the Lclutch teeth 36 of the reversedrive bevel gear 32 when the shift collar 45 is moved tothe left (FIG. 2).' Similarly, the shiftwcollar 45has `a set of forward clutch teeth 48 which are drivingly engageable with the clutchteeth 37 of the forward drive bevel gear 33when the shift collar 45 is moved to the right (FIG. 2).

Thus, a forward drive will be completed from the driving bevel gear 20 tothe shaft 40 through the forward drive bevel gear 33 andthe shift collar;45 when the shift Vcollar 45 ris moved tothe right so Vthat the clutch teeth 48 thereof are in engagement with the clutch teeth 38 of the forward` drive bevel gear 33. Similarly, a reverse drive will be completed between the driving bevel gear 2t) and the shaft through the reverse drive bevel gear 32 and the shift collar when'the shift collar 45 ismoved to ment with the clutch teeth 37 of the reverse drive bevel gear 32. Also it shouldrbe noted that a neutral condition is obtained byv centering the shift collar between the` Areverse drive bevel gear 32 and the forward drive bevel gear ,33 as shown in FIG. 2. In this position the reverse andforward kdrivebevel gears 32 and 33 will rotate in response to the drive bevel gear 20, but no power will be transmitted to the Yfloating shaft 46 through the shift collar 45. The clutch'teeth of the shift collar will not be in engagement with either set of clutch teeth 36 or 37 of the Vreverse drive bevel gear 32 or the forward drive bevel gear 23. v

A Shift linkage marianista is provided (FIGS. 1 5) f for. the purpose of shifting the collar 45 on the shaft 40 to derive the desired drive or neutral condition. This linkage provides, among other things, a guide shaft 'supported in the head casing 12 in openings 56 and 57 parallel to the shaftl 4t). A shift fork 5S is slidably bevel gear 32 is rotatably supported in the left side of the headcasing 12 (FIG. 2) by the ball bearing 31. `A forward drive bevel gear 33 s similarly rotatably supported in the ,right side of the head casing 12 .by the otherball bearing 371. The reverse drive bevel gear 32 has a setof drive yteeth 34 in continuous driving engagementl with the driveftee'th 21 of the driving bevel gear 20. The forward drive bevel gear33 has'a similar.` set of drive teeth 35 which arel also in continuous driving engagement with they that the reverse and forward drive bevel gears 32-.and 33 are aligned and in continuous driving engagement with the drive bevel gear 20 on opposite sidesthereof. A reverse and forward drive are thereby provided VVon a single axis common .to both.y i

45 It should benoted mounted Von the shaft 55. through a cylindrical kinternal passage 59 and has apair of prongs 60 extending slid ablyinto an `annular groove 61 in the shift collar 45. Thus, axialmovement ofthe shiftfork 58 on the shaft 55 will cause the prongs 6i) to move the shift collar 45 onl the .shaft 40. This movement is designed to result in engagefment or disengagement of theclutch teeth 47 or 48 of the shift collar 45 with the clutch-teeth'37 or 38 of the re verse or forward drive bevel gears 34 or 33 respectively. A manual shifting means is provided as part of the shift mechanism (FIGS. 1-5) andy is adapted 'for selectively The reverse and forward drive bevel gears 32 and 33 j are providedgwith `clutch teeth36 and 37 on the respec. tive facingtinner radialsurfacesthereof. VBoththe reversedrive bevel gears 32 andthe forward drive bevelgear33 have a shoulder 38 (FIG. 2) in engagementwith the respective-roller bearings 31 to prevent outward movement ofthe reverse and forward bevel gearsr32 and; 33;

A retainerring 39 is provided on'both the V.reverse and-ff forward drive bevel gears 32 and 33 immediately adjacent therespective roller bearings 31 to prevent inward'axial movementl of thereverse and forwardbevel 'gears 32:" and33. i Y

1- An Vidlerushaft 4,0"havng Ya-splined Vperipheral surface; "41 is concentrically rotatably mounted iniatpair ofiaxially aligned cylindrical openings 42 and 43 in*V the reverse andf forward drive bevel gears- 32 and 33 respectively. The shaft 40 has an end portion 44 extending to the left (FIG. 2) beyond the reverse drive bevel gear 32 and the head* casing 1:2. n 'L In order to select either` `the forward or reverse driveY from the reverse o r forward bevelfgears 32 and 33`and apply it to the shaft 40, a shift collar 45 is provided. They' shift collar 45 is splined to the shaft 4t) by an internal spline 46 and is thereby drivingly connected to the shaft the'boat adjacent thetransomlS (FIG. 1).,Vv A radially moving the shift fork 5S on the shaft S5. The' manual, shiftingV means includes a torque shaft rotatably mountedin a cylindrical passage 66 of the head casing 12 (FIGS. .1, 3 and5). Ashift lever 67 is rigidly secured to the'torque shaft 65 and extends laterally therefrom inside extendingcam iskeyed to the inner end of the torque shaft 65by means of a flattened surface 71 on the torque shaft 65 adjacent theinside of the head casing 12'. As

` the shift lever 67 is rotated clockwise about theV axis'of the torque shaft from forward position to reverse po sition V(FIG. 5) the 'cam 70fwill consequently be moved likewise.` j l The vcam 70 hasa series of notches 72, 73 and 74 in the peripheralsurface 75 thereof (FIG. 5) adjacent a springv biased ball detent 76 whichis mounted in the `opening 77 Vof the head casing 12.r The ball, detent 76 engages the series offnotches lf2-'74 yas. .the cam .70 is rotated in y.response-5to rotation of the shaftglever 67. Thus, the detent positions the cam in'oneiof three positions,.namely,. forward, neutral or reverse in vresponse to the.' entry of the ball detent intoone ofthe notches 72,73 or 74 respectively,VY depending on' the selected position ofY the -shift lever 67. i Y' f A A yoke Si) is provided` forf'transmitting the'oscillating n movementof the shift lever 67 into a reciprocating shift positioning movement of the shift fork 58, along the shaft 55. The yoke 80 has a pair of aligned openings 81 in the K legs thereof which slidably support the yoke on the shaft 55 with the base of the yoke 80 adjacent the end of the torque shaft 65 (FIG. 3). The end of the torque shaft 65 has a reduced concentric Vcylindrical portion 32 extending therefrom into a slot 83 for' slidably supporting the yoke. The slot 83 is parallel to the shaft 55 upon which the yoke 80 is slidably mounted. An eccentric lshift pin 84 is provided on the cam 70 and extends therefrom parallel to the axes of the torque shaft 65 into a vertical slot 85 in the yoke 80. The slot 85 is perpendicular to the slot 63 of the yoke S0. `V

With this interconnection between the torque shaft 65 and the yoke 80 through the cam 70 andthe eccentric shift pin 84, it can be readily seen that oscillation of the torque shaft 65, by pivoting lever 67, will result in a similar oscillation of the eccentric shift pin 4 in the slotSS. The yoke will consequently be moved horizontally by the eccentric shift pin 84. Inasrnuch as the yoke S is restricted to reciprocating motion by virtue of the supporting shaft 55 and the supporting concentric pin 82 in the slot S3, the yoke 80 will be reciprocated on the shaft 55 in response to the oscillation of the shift lever 67.

The reciprocating movement of the yoke 80 is Vtransmitted to the shift fork S by either one of a pair of coil springs 86 and 87 (FIGS. 2 and 3). These springs S6 and 87 have one end thereof in engagement with the left and right legs of the yoke S0 respectively (FIGS. 2 andr3). The other ends of the springs 86 and 87 are positioned around a respective cylindrical surface 33 or 39 and against a shoulder 90 or 91 of the shift fork 5S.

Thus, the reciprocating movement of the yoke 80 resulting from the( oscillating positioning of the shift lever 67, as before described, will result in a spring engaged shift of the shift collar 45. More particularly, when the shift lever 67 (FIG. 5) is moved to the reverse position and cam notch 72, representing the reverse notch, will be held by the detent 76 and the4 yoke S0 will thereby be v positioned to the left (FIGS. 2 and 5) on Vthe shaft 55. This will result in an engagement of the shift collar clutch teeth 47 with the clutch teeth 37 of the reverse drive bevel gear 32 andr will provide the reverse drive from the driving bevel gear 20 to the oating shaft 40. y

When the gear train is in reverse condition, and engine torque is applied therethrough, a movement of the shift lever 67 from :the reverse position to the neutral or forward position will result in movement of theV yoke 80 from its left position (FIGS. 2 and 5) to extreme right or forward position. If the engine drive torque remains sufciently high, a force will be applied between the meshing clutch teeth 36 and47 and the shift collar 45 which will prevent disengagement of the reverse drive bevel gear 32. The spring 86 will be compressed and thereby apply a bias to the shift fork 58. When the engine torque is sutiiciently reduced so as to release the force on the clutch teeth 36 and47, the spring bias will cause the fork to move the shift collar 45 to a neutral position or to forcef ably complete engagement between the clutch teeth 48 and the forward drive bevel -gear clutch teeth 3S, to com-` plete a forward drive train from the drive bevel gear 24 to the floating shaft 40. A similar operation will occur f when the shift lever 67 is moved'from forward to reverse or from neutral to either forward or reverse, regardless of the load condition, and the shift will eventually be accomplished without causing an improper meshingof gears under hightorque conditions. This .avoids any harsh destructive vibration in the linkage which would'be felt by theV operator through the shift linkage as he moved Vthe shift lever 67.l Y

The intermediate casing 13-illustrated in FIGS. 1, 2 and 4 is pivotally connected to the head casing 12 so as to pivot about the axes of the floating shaft '40 ofthe head casing 12. To this end it should be noted that the intermediate casing 13 has two concentric cylindrical inner surfaces 100 and 101 which are slidably mountedv on a pair of complementing surfaces 102 and 103 on the pe l tion in the Water or is otherwise moved to position the* 6 riphery of the left and right bearing retainers 30 (FIG. 2). The head casing 12 and the intermediate casing 13 are thereby interconnected by a fulcrum` or pivot joint sov enlarged annular portion 106 is formed on the left side (FIG. 2) of the intermediate casing 13 and a cover plate 107 is rigidly secured thereto to enclose the surface 100 and the opening presented by the enlarged annular portion 106. The cover plate 107 also acts as a bearing support for a bearing 108. A bevel gear 109 having teeth 110 is splined to the shaft 40 and is supportedby the ball bearing 108. The bevel gear 109 and the shaft 40 are held against relative axial movement therebetween by retainer A rings 111 appropriately placed on the bevel gear 109 and the shaft 40. The intermediate casing 13 is provided with a bearing retainer 115 (FIGS. land 2) which extends laterally therethrough. A roller bearing 116 is held by the bearing retainer 115. Another bearing retainer 117- is secured toA the intermediate casing 13 by bolts 118 and is utilized'to support a ball bearing 119. A bevel gear 120 is rotatably supported by the roller bearing 116 and the ball bearing 119 and has a set of teeth 121 in meshing engagement with the teeth 110 of the bevel gear 109. The bevel gear 120 has asplined internal passage 122 which is concentric with the axis of rotation thereof. p

. The bevel'gear arrangement, just described, and the fulcrum connection between the lintermediate casing 13 and the head casing 12, provide a forward and reverse drive train selectable by the shift lever 67 and which is complete from the driving bevel gear 20 to the shaft 40 regardless of the position of the intermediate casing 13 as it is pivoted about the fulcrum connection described v above. Such pivoting of the intermediate casing 13 may occur in the event the propeller casing strikes an Aobstrucin this position in the'cavities 131 and 132 by bearings 133 and 134 respectively.

A helical gear v135 is formed on, o'r' otherwise mounted to, the cylindrical portion 130 and has radial faces 136 and 137 thereof in contact with a radial-surface 138 and 139 on the bearing retainer v117 and thelower portion of the'intermediate casing 13 respectively. The gear` 135 `thereby retains the cylindrical extension 130 of the propeller casing 14, against longitudinal movement within the intermediate casing 13. The'bearings 133 and 134 rotatably support the cylindrical extension of the propeller casing `14 so as topermit vthe entire propeller` casing 14 to be `rotated within theintermediate casing'13l- A steering; mechanism is provided fort-1e `driveunit 51 which comprises a mechanism `for rotating the casing `1K1 within the intermediate casingV 13 in responseto-a steering 4wheel or similar device.. A worm gearfhousing 145 f is, provided (FIGS. 1, 3 and`4) on the intermediate cas-,jf` ing 13. A worm gear 146 Ais rotatably supported jin' the-` worm gear'housing 145 by lball bearings V147 andbear-j ings' 143. The worm gear 146 has a set lof teeth 149 in engagement witha set of teeth 150` ofthe spur gear 135 (FIG. 3). vA flexible shaft 151 isY drivingly connected at one end thereof' to the worm 'gear 146 at`152', and atthel other end thereof to a pulley coupling 153. The pulley `in turn Yis mounted in the transom of the boat. The

by ange 157 and the other `end thereof secured to a( plate 158 also. held to the transom by bolts 155. The

pulley coupling 153 is drivingly secured to a pulley shaft 159 which in turn is drivingly connected to a pulley 160. The pulley 160 is operatively connected to` a steering wheel by'cables or other means well'known in the marine eld which will cause the pulley to respond to a steering wheel.

It should be noted `that by rotating the pulley, the flexible shaft 151 will rotate the worm gear. 146 and thus the helical gear 135, to rotate the entire propeller housing 14 within the intermediate housing 13. Inasmuch as this drive between'the pulley and the gear 146 is flexible, it is possible to rotate thepropeller casing 14 within the intermediate casing 13 regardlessof the pivoted position of the intermediate casing 13, relative to the head casing 12. To extend the drive .train from the. bevel gear V125i through the propeller casing 14, there is provided a vertical ,propeller shaft (FIGS. l and 2) having a splined i upper end 171`drivingly engaging the splined internal pas# sage 122 in the bevel gear 120: Theshaft 1717 has a lower end 172 rotatably mounted in a ball bearing 173. The l ball bearing 173 Vis rigidly mounted Vina bearing retainer 174 which is part of the propeller casing 14. A bevel gear 175 having teeth 176 is rigidly secured to the lower endv 172 of the vertical propeller shaft 170 and is positioned in.

a cavity 177 in the propeller casing 14. f K Y A horizontal propeller shaft 178 is rotatably mounted in bearings 179 and 180. The bearing 179 is mounted in.

the propellerhousing 14 and the bearing 180 is mounted in a bearing retainer cap 181. The shaft 178 extends to the right beyond a propeller housing 14 (FIG. l). A bevel gear 182 is drivingly mounted on' the horizontal propeller shaft 178 and has a set of teeth 183 in meshing engagement with the teeth-176 of the bevel gear 175. A propeller 184 is keyed in a-conventional manner toV the horizontal propeller shaft 178 and is held against axial movement thereon by ya nut 185 threaded onto the shaft 178. Thus, it can be seen-that the reverse or forward rotary motion imparted to the bevel gear 121), as previously described, will be transmitted to the propeller 184 through the shaft 17.0 and bevel gears 175 and 182. Once again it is pointed out that this drivingtrain will remaincornplete in all positions of the intermediate casing 13 and propeller casing 14, as the intermediate casing 13 is pivoted about the head casing 12. r

' VIt should be noted that although applicant has illustrated a one-to-one gear ratio drive trainthrough the unit, the unit is not necessarily 'sorlimited The bevel gear 28;, :or v169, may be reduced in Asize to provide agear reduc` -tion in the drive train without resorting to adjacent oiisetl In lthe past it has beenY drive shafts kin the drive train. necessary toY resort to .such an offset in the drive'shafts axis' thereof in'` a central' ,0r` other lverticalplane-'of V.the

not necessarily limited. to onlyfour positions. For thisy V205 extends downwardly and away'from the transom 15 torprovide two projectingV positions 207, 'one of which is.

.when a gear reduction'was to be had. Applicants drive y unit allows theending to bel mounted withstlie drive shaft 60 boat with the intermediate drive shaft 170 operating in; ythe same plane withoutfany lateral horizontal offset., f Referring tol-"I CVS'.` 4`, 6, 7 and 8 thereisillustrated a lmechanism for releasably ,positioning the' intermediate. :and propeller casings 13 and14'in any oneof Several.

down positions. For purposes of illustration, only lounk s uch positionsare described, Yalthoughthe rnechanismisVV on. the left and one 'of which is on the right (FIG. 2) of.

the intermediate casing .13. 210, 211 and ",212 are formed in the bottom of .eachro A series of four notches 209,

' head casing` 12.

i i a i the extensions `207 in a circular .path having a center coincident with the pivot axis of the intermediate casing 13. The notches 209-212 on theleft are respectively aligned with the notches V209-212 on the right.

Y It should be'further notedthatthe propeller casing 14 comprises two sections; namely an upper section 142 and the lower section-146.- These sections are held together along a parting line 190 by bolts 191 threaded into section 146. This divided arrangement of the propeller casing 14 provides a means whereby the length thereof can be adjusted by spacers (not shown) positioned between the sections 142 and 146 along the'parting line 190. Also,

this arrangementfacilitates adjustment and other mainjustably pivoting the intermediate casing 13 about they Y head casing 12.

ings 214 open downwardly and forwardly so that there is a forwardlyrprojecting shoulder 215 adjacent the lower It should be notedV that the hook openportion ofthe opening 214. Y

A pair of lJ-shaped links 215 (FIGS. 2-6 andv 7) are provided which are pivotally and slidably mounted in respective extensions 207by means of a pin 217 rigidly secured to each link -216 and slidably inserted in a slot 218kv inthe extensions 207. The slot218 is positioned along a radius of the common pivot axis of the intermediate and head casing's 13 and 12. Each pin 217 (FIG.,2)

has a ange 219 cylindrical body 220, a shoulder 221 and a reduced threaded end portion 222. The flanges 219 are positioned on the inside ofthe respective bracket projece` tions 207 with the vcylindrical body 220 slidably positioned` y in the respective slots 218, the reduced threaded end portion 222 extending'through an opening 223in the 'adjacent` link 216 and the shoulder 221V abutting the inside of the K respective links 216. The retainer pins 217. are secured to the respective links 216 by against the links 21,6.'V

The links216 are interconnected by a lock rod 225` (FIGS. 1-6-and 7.) whichis inserted in pairs of aligned `'openings 226 in theA links 216. The rod 225 isheld in place' by pins 227 at each end thereof. ,It should be noted that the .rod spans-.the two "setsfof alignednotches 209- 212 and -is adapted to lfit in the aligned notches 209-212 fand theraligned hook'openings 21'4. I For purpose of illustration, the lock rod 225 is shown positioned Yin Vthe aligned notches 209 which represents the forward most position. of the intermediate casing 13,]with the propeller shaft170.. held ina substantially verticalposition. e v

Thus, the links '216, lockrod 22S secured thereto, and the retainer pins 217 secured to the links 216, form a rigid frameworkwhich is vertically v,movable to the extent of the length of the yslots 218V inthe bracket'projections 207... v The length of the slots V21,8"is `suiiicient toallowlthe lock rod 225 to move downwardly beyond the aligned, notches 209 and the aligned openings 214to allow repositioningl A movement yof the lock-rod 225 in one of therother pairsof aligned notches 210,211, or 2,12. l

that the lock rod 225 willfrelease the hook 213 Awithout, the lock 'rod 225being completely removed Vfrom these-1 lected positioning notches 209, inasmuch as the upper por- .tion ofthe hook vopening 214 does not extend downwardly as far as thev notches 209-212. This allows a position Yindex determined by a pair of aligned notches 209*212 to be maintained while the intermediate Vcasing 13 is pivoted counter-clockwise (FIGS. 7 and 8) about the a'sdetermined. n

a nut 224 which is tightened It should be notedy Uponreturn of `the casing` 14 to its f i down position thelock rod will position the casing 14so A pair of spring retainers 230 (FIGS. 2, 4 and.7) each have a passage 231 byV which the retainers 230 are rotatably mounted on the respective retainer pins 220. The spring retainers 230 are slidably movable in respective openings 232 in an arcuate portion 233 of the respective bracket projections 207. A compression spring 234 is retained on each of the spring retainers230, between the arcuatesurface 233 and an enlarged upper portion 235 of the spring retainer 239. The compression springs 23,4 tend to force the spring retainer 230 upwardly with respect to the arcuate surface 233 and thereby tend to force the respective spring retainer pins 217 upwardly in the slots 218. The pins 217 in turn urge the lockrrod 225 into the selected notch 269 of the series of notches 209-212 and the openings 214 of the hooks 213.

Thus, a spring bias lock or detentis provided for holding the intermediate casing 13 against rotation about the head casing 12, but which is releasable by movement of the lock rod 225 against the action of the compression spring 234. This feature is important in the event that an obstruction is 'engaged by the propeller casing 14. In that instance the intermediate casing 13 would be urged to the right (FIGS. 6 and 7) resulting in a force exerted by the upper side of the hook opening 214 against the lock rod 225 to force the lock rod 225 against the incline sides of the notches 299 and thereby tend to force the lock rod 225 ont of the notches 209 and the hook opening 214,y

against the force of the compression spring 234. If the obstruction force thus exerted is suiiicient, the lock pin will be forced completely out of the hook opening 214 and the intermediate casing will be free to rotate countera counter-clockwise position, it would be` necessary torev lease the pawl 243 from the ratchet pattern by depressing the release button 248 toforce the pawl 243 out ofthe ratchet pattern. Thus the lever 241 can be adjustaby moved in a counter-clockwise direction at will, but Will be releasably held against a clockwise rotation by virtue of the ratchetv 249 and the pawl 243. J f

A partial drum 260 having an axis parallel to the pivot taxes of the lever 241, is rigidly secured to the lever 241 by a bar 261. Thus, by oscillating the lever 241 in a counter-clockwise direction about the pin 242 the drum 269 will be oscillated likewise. A cable 262 is pivotally connected to the upper portion of the drum 260 atr263, and extends through the transom 15 and a guide-way 264 on the casing 13. The other end of the cable 262 is pivotally connected to a pair of levers 265 at 264cz.v The levers 265 are Vpivotally mounted on the sides of the intermediate casing 13 by means of bolts 2.66 (FIGS.

The levers 265 have a cam surface 267 and flat portion 263. VBy pivoting the lever 241 counter-clockwise clockwise (FIGS. 6 and 7) to allow the intermediate and propeller casing 13 and 14 to kick-up. Thus the unit can be releasably positioned in any one of the notches 209-212. v

It should be noted that the shoulder portion 215 on thehooks 213, will tendrto hold the lock rod 225 in any pair of the selected notches 209-212 when the intermediate casing 13 is urged clockwise about the head casing 12. This situation would occur when the propeller exerts` reverse thrust and would tend to hold the lock rod 225 tightly in the selected grooves 209 instead of forcing it out of the grooves as would a force exerted against the intermediate casing 13 in `a counter-clockwise direction, as by an obstruction as previously described.

This embodiment of applicants invention'provides a means for moving the lock rod 225 to release its locking effect on the intermediate` casing 13,VV and to raise the intermediateA casing 13 by causing it to pivot about the head casing 12. To this end there is provided a bracket 246 secured to` the inside of the transom 15 (FIG. 6) and extending inwardly therefrom. A lever 241 is pivotally mounted to the bracket 240, by means` of a pin 242. A pawl 243 is pivotally mounted to the lower end of the lever 241 on a pin 244. The pawl 243h`as a dat sided vrtooth 243a and is pivotally connected toa release rod-245 at 246. t v g Y AThe release rodl245 extends upwardly through a hand grip 2'47 formed on the upper portion of the lever 241 and terminates in a release vbutton 248. The release'rod '245 is spring" biased upwardly'byV a spring (not shown) containedV in the hand grip 247 so as'to urgethe. pawl243 against the bracket 240."The bracket 240 is provided withv a'ratc'hetppattern 249 formed on a partial circle having an axis 'coincident with that Vof the pivot pin 242. The ratchet pattern 249 comprises a series of teeth 250 having a directionalcharacteristic to the extent that one side 251 is inclined to the radius of the ratchet pattern and one side 252 is positioned radially with respect to the radius of the ratchet pattern. The tooth243av of the pawl 243 hasone side-'253 whichis adapted to cornplement the radially' positioned sides 252 of the ratchet teeth 250 and another side 254 which is adapted to clear the inclined tooth sides 2,51.

f treme up position of theintermediate'casing13.when

- cause the leversr'265V to release the lock rod 225 from;

(FIG. 6), the cables 262 will be taken up on thepartial drum 260 and as a consequence, the levers 265 will be pivoted counter-clockwise until the ila't surfaces thereof engage a stop 269 on the respective sides of the intermediate casing 13. During this counter-clockwise movement of the lever 265, the cams 267 will engage the respective retainer pins 217 (FIG.v 7) and move the retainer pinsrdownwardly in the respective slots 218 against the resistance of the respective compression springs 234, and release the lock rod 225 fromits locking position in the openings 214 of the hooks 213., v

Thus, the movement required to `pivot the lever 265V Y from the position shownin FIG. 6 to that showny in FIG. 7,Y will cause the release of the positioning lockV rod. A continued counter-clockwise pivotal .movement of thelever 241 will cause the cable 262'to raise thev intermediate casing 13 inasmuch as the lever265 is restrained'against further rotation inthe counter-clockwise direction by the stops 269. FIG. 8 illustrates the ex-g the lever 241is pivoted counter-clockwise to the maxif i mum position.` The intermediate casing 13wili bere-V tained in this Yposition by the ratchet and pawlV 249 andfA button' 248 is depressed .to release the pawl 243 from the ratchet:v 249, the lever '241 is rotated counter-clockwiseto;

the hook 5213.' Continued counter-clockwise rotationA of the levers241 will pivot the intermediate casing"13.abo'ut.f

the headcasing`12 to a selected position determined by the ratchetfand pawl'249 and'243with the extreme position Vbeing that shown in FIGQS.

' It is to benotedthat thei'lever andzratchet'rneans previouslydescrib'ed, can be used to raise the casings andy 14 from any one of the down positionsdeiined by the notches' 209412 to an intermediate position determined by the ratchetv 49 in the Vevent that the boat isto b e operated in shallow water. In any such intermediate p osition, the propellerand intermediate casings 14 and 13 may kick up upon hitting an obstruction, inasmuchas these casings are free"t0 pivot counter-clockwiseV about;4

A positive reverselock mechanism (FIG. 4) is pro- Y 1 l Y videdin this embodiment 13 and 14 about the head casing 12 when the reverseA drive train-is. completed. j. This positive reverse lock includes a hook 275 (FIG. 4) pivotally mounted topth'eright bracket projection 207 (FIG 2) by a bolt 276;"Thephook 275V is urged upwardly lby .a tension springl 277 which is anchored to a pin 278 inthe hook 275 and an opening 279`in the bracket 205.

The outer end of the hook 275 has a tip 280 projecting laterally therefrom and adapted to' engage any onevof a series of teeth 281 formed in a bracket 282 which is rigidly secured to thecasing 13 by a pair of'bolts 283. The teeth 281 are positioned on the bracket 282 so as to cor- Vrespondjwith the positions determined by the notches 209-212 of the break-away,rpreviously described. The

transmission will thereby be normally held against 'breakof applicants* invention, Vto pre- Y vent the rotation of the intermediate and propeller casings` away by virtue of the spring `biased hook 275 engaging .f

the corresponding tooth 281' in each selected break-away position.

A rod 284 is pivotally connectedy tothe hook 275 at 285 and (FIGS. 3 and 4) terminates in a'ball socket 286.

A lever 288 is secured to a shaft 289 which is rotatably mounted in a passage 290 of the head casing 12 (FIG. 4). A reverse lock cam follower 291 isrigidly secured to the other end of the shaft289 by means of anut 292 Athreaded on the end of the-shaft 289 (FIGS. 3',Av 4V andfS). `The re-V verse lockV cam follower 291 terminates in a tip`293, extending `laterally therefrom (FIG. 5) toward the cam 70 of the shift linkage. The cam .'70`has a raised camsurface 294 and a depression surface 295 on the side thereofk adjacent the follower tip 293.

In operation vof the reverse lock, above described, the control lever 67, when moved to the reverse (REV.) position (FIG. 5), the cam surface 294 will be rotated out'of soa (FIGS. 9 aad-1o) which is substituted forth@ coverplaie 107 (FIG. 2). 1

rl'he retainer 300is secured totheenlarged flange pori tion 106 of the intermediate casing 13 and supports the bearing 108 and bevel gear 109; A pilot hub 301 is provided on the bearing retainer 300 and has a cylindrical surface 302 extending outwardly therefrom about the axes of the idler shaft'40.` A stop 303 provides a partial cylindrical surface 304, coincident with the surface 3020i the hub 301, and a flat chord surface 305.

A segmented gear 306 is rotatably mounted on the coi inciding cylindrical surfaces 302 and 304. A snap ring 307 is provided on the stop 303 to retain the segmented Vgear 306 on the cylindrical surfaces 302 and 304.A The Y' bearing retainer 300' and rotatablysupports a worm gear 316having'a set of teeth 317 in meshing engagement with teeth 318 of the segmentedgear306. The worm gear 316 isconnected to a shaft structure 319 which extends through the transom 15 and is'drivingly connected to a crank 320., Rotation of the crank 320 in a clockwise direction, looking towards the stern of the boat,'will rotate'theworm gear 316 so as to cause" the-segmented gear 3,06 to rotate! counter-clockwise (FIG. 9.). Similarly, the counter-clockengagement with the` follower tip 293. Under these conditions, the tension spring 277 vfwill urge therod 284 upywardly and` pivot the lever 288 counter-clockwise (FIG.

5) and move thetip 293 against thedepressionssurfa'ce 295. Thus, the cam 70 will allow the hook 275 toV pivot j about the kbolt 276under the Vforce exerted by the spring 277 and theV tip 280 will move `into positive-'locking env -gagement with a tooth 281 which represents vone of the positionsof reverse lock.' The shifting f the transmission into Yreverse will thereby YVlock .the intermediate casing and propeller casing 13; and 14 against clockwise` rotation (FIG. 4).

tip 293 and rotate the cam follower291 andthe lever`288 in a clockwise direction. ThisYL movement of lever 288 will pivot the hookY 275 counter-clockwise aboutthe bolt 276 andthereby releasethe hook tip 280 from-engage-l ment with the selected tooth 281 to allow the'intermedi-- 'ate and propeller casings 13 and 14;' to .rotate .-clockwiseV about the head casing 12, except.v for the releasable"forceY exerted by the break-away lock rod225. i'

peller casings 13 and 14 .will'be held against clockwise Yrotation (FIG. 4) and4 allow the boat to be drivenu in reverse. Vforward or the neutral position, thereversey lock. hook 2,75 will be released to allow the unitl to beheld by 'the releasable lockrod 216 subjectto kick-upupon hitting au-A obstruction.'

Y Another embodiment of applicants invention isrillus` trated in FIGS."9,- l0 and ll and provides the reverse lock' and break-away detent, previouslyrrdescribed, and illustrated in reference v.to FIGS. 2-8. f The present embodi-r ment is designatedas a worm gear lraise up and is anadf "When eitherthe forward or neutral positionslfare selected by the control lever` 67, the cam 70 will be rotatedv y,

`so that the cam surface 29.4 will engage the` cam `followerV 50 f Thus, it'can be seen that when thecontrol1lever-67 is ro-Y j tated-.to the reverse position, thefintermedate andgpro-j 6,0

Whenl the control leverV 67 is moved -to either justment for pivotally positioning.the'ntermediate and propeller shafts 13 and14 about the head casing 12. This raise-up includes, among other things, a bearing retainer wise rotation of the .crank 320 will cause a clockwise r'otation of the segmented gear 306.

Gravity urges the intermediate and propeller casingsflA and' 14 in a clockwise direction so that the upper portion of the chord surface 305 willnormally engage the flat .surface 310 of the ltang 3019. The positionrof the tang 309.

will thus determine the .maximumk down position of the intermediate and propeller casings 13and 14. It is to be noted that the stop 303 is free to Vrotate from this position to one where the lower portion of the chord surface 305 is in engagement'with the at surface of the tang k309 in the event the unit'strikes an obstructionV and the intermediate and propeller casings are thereby urged counter-clockwise aboutthe head casing 12. y.

In operationptoV lower casings 13 and'14 from Lthe raised position shown in FIGURE 9, "to the intermediate position represented inV FIG. 1v1 or .to a down position, .the

' crank 320 is rotated in a .counter-clockwise direction' look-v ing towards vthe stern of the bo at,- resulting ina clockwise rrotation ofthe segmented -gear 306 in response to the worm gear 316V. The gravitational effecten the casings 13fand 14Vwill cause a clockwise rotation of the casings 13 and'14 and the kstop 303ther'eof, in a clockwise direction with` the upper portion of the chord 'surfaceg305 tin engagement with the at surfae310of. the'driving tang .309. -Thus,.anyintermediate or down attitude of the cas- Y ings 13- and 'i4 wnrbe Qbtaint-aa's indieaied in FIG. 11.

` In the substantially down positions of the intermediate and f propeller casings13and 14, the reverse lock and break-v, away mechanism will beefiective intheir normalV manner? toy releasably,V retain the` casings. I l FIGS.. 12, 13 land' Y14 illustrate. another embodimentA of applicants sterndrive having-a break-away andreverse lock mechanism in-'conjunction'withi either the ratchet or lthe worm gear positioning mechanism as previously described;y y

Y The breakwaymechaaismshown in FIGS. 1244 includes, among otherthings, a plate 325 mounted on the transom 15 having'a pair of brackets 32.6 and 327 extending substantially perpendicular therefrom and respectively adjacentV the left and right sidesof the intermediate casing 

1. A MARINE OUTBOARD DRIVE UNIT FOR A BOAT HAVING AN INBOARD ENGINE AND COMPRISING THE COMBINATION OF A SERIES OF THREE INTERCONNECTED CASINGS, A FIRST CASING BEING MOUNTED ON THE BOAT, A SECOND CASING BEING PIVOTALLY CONNECTED TO SAID FIRST CASING AND ADAPTED TO PIVOT ABOUT AN AXIS THROUGH SAID FIRST CASING, SAID SECOND AND A THIRD OF SAID CASINGS BEING ROTATABLY INTERCONNECTED, A GEAR TRAIN MOUNTED IN SAID CASINGS FOR PROVIDING A FORWARD AND REVERSE DRIVE, SAID GEAR TRAIN HAVING A DRIVE SHAFT IN SAID FIRST CASING ADAPTED TO BE DRIVEN BY THE ENGINE AND A PROPELLER SHAFT IN SAID THIRD CASING ADAPTED TO DRIVE A PROPELLER, SAID GEAR TRAIN INCLUDING A FORWARD AND A REVERSE GEAR IN MESHING ENGAGEMENT WITH A DRIVE GEAR ON SAID DRIVE SHAFT AND ROTATABLY MOUNTED ON A HORIZONTAL AXIS PERPENDICULAR TO SAID DRIVE SHAFT TO PROVIDE FOR PIVOTAL MOVEMENT OF SAID SECOND CASING WITH RESPECT TO SAID FIRST CASING ABOUT AN AXIS PERPENDICULAR TO THE AXIS OF SAID DRIVE SHAFT MEANS FOR SELECTIVELY SHIFTING SAID GEAR TRAIN BETWEEN FORWARD AND REVERSE, INDE- 